As the miniaturization of microelectronic circuits approaches technical and economical limits, extensive efforts have been made to develop devices based on nanowires such as, for example, carbon nanotubes. Nanowires are typically synthesized in a solution or a powder form. To build devices from nanowires, the nanowires often have to be deposited on a substrate with particular positions and orientations.
Existing assembly processes for depositing nanowires sometimes require direct manipulation of the nanowires via nano-manipulators or alignment of the nanowires via an external force, such as, for example, using a flow cell or an applied electric field. Assembly processes requiring use of nano-manipulators are slow processes and are generally not suitable for industrial applications. Assembly processes requiring use of an external force can be used to deposit nanowires on a substrate with a particular orientation. However, requiring use of an external force adds an additional processing operation, which increases assembly time and costs. Moreover, it can be difficult and time-consuming to deposit nanowires with different orientations on the same substrate using an external force.
It is against this background that a need arose to develop the processes and nanowire-based devices described herein.